In recent years, touch panels and display panels and display devices with a touch function have been increasingly popular as they become user-friendly, convenient and prompt to operate. The touch panels can be categorized by their different operation principles into, for example, a resistive-type touch panel, a capacitive-type touch panel, an electromagnetic inductive-type touch panel, etc. Particularly, the resistive touch panel and the capacitive touch panel are advantageous in their possibility of being operated directly with a hand or finger. However it may be difficult to distinguish touching by the hand or finger from touching by a stylus while writing with the stylus because the hand or finger is generally placed on the touch panel. The electromagnetic inductive touch panel generally includes a plurality of electromagnetic inductive coils or antennas disposed in the X and Y direction and a positioning device (e.g., an electromagnetic stylus). The position of the electromagnetic stylus can be determined accurately by the electromagnetic inductive touch panel even if the hand or finger is placed on the touch panel.
FIG. 1 illustrates a schematic diagram of a circuit structure of a conventional electromagnetic inductive touch panel. As illustrated in FIG. 1, the electromagnetic inductive touch panel includes a plurality of X-direction detection lines 11, a plurality of Y-direction detection lines 12 insulatedly intersecting with the plurality of X-direction detection lines 11, and a plurality of coils 13 disposed in a matrix (e.g., a 3×3 matrix of coils as illustrated) to be respectively at the intersections of the X-direction detection lines 11 with the Y-direction detection lines 12. Each of the coils 13 is provided with two ends including one end connected with both a corresponding X-direction detection line 11 and a corresponding Y-direction detection line 12, and the other end grounded through a common electrode line 17. Each of the X-direction detection lines 11 and each of the Y-direction detection lines 12 are connected with a corresponding X-direction detection circuit 15 and a corresponding Y-direction detection circuit 16 through a current amplifier 14. If an electromagnetic stylus induces inductive current in some electromagnetic inductive coil 13, then the inductive current will be detect by the X-direction detection circuit 15 and the Y-direction detection circuit 16 to thereby determine the coordinates of the position where touching occurs.